The traditional Chinese herbal medicines are in the forms of liquids prepared by decocting crude drugs (), powders prepared by powdering crude drugs or pills made of crude drugs and honey. Therefore, traditional Chinese herbal medicines have the disadvantages of being inconvenient due to the time required to decoct crude drugs, and due to having to prepare it according to necessity. Furthermore, it is painful or difficult for a patient to take the decoction or the powdered crude drug, due to the bitter taste or smell, which are peculiar to Chinese herbal medicines. Today, in order to solve such problems, Chinese herbal medical preparations, such as extracts from a Chinese herbal medicine, powders, granules, tablets, liquids, etc., are prepared starting from the powdered crude drugs. These preparations solve the inconveniences due to taking time to decoct crude drugs, and having to prepare it according to necessity. These preparations are also superior in preservative stability.
However, a patient must take several grams of preparation in the form of powders, granules or tablets, and this is a burden for the patient. Further, the powders and the granules can cause problems such as choking, resulting in a sandy feeling in a mouth, or getting between false teeth when they are taken. The tablets can be too large for a patient to take. The taste and smell peculiar to a Chinese herbal medicine is improved by tabletting it. However, there are still disadvantages in that a Chinese herbal medicine is strongly tasted, is unpleasant, and is difficult to take when the contents in the tablets dissolve, or the tablets disintegrate in a mouth while taking them.
On the other hand, the liquids are more easily taken compared to the powders, the granules and the tablets. However, the liquids have troubles in that the bitter taste and smell peculiar to a Chinese herbal medicine becomes strong, because the liquid is broadly spread in a mouth. Therefore, it is painful and difficult to take a liquid formulation. Furthermore, it is inconvenient to carry as it is packed in a glass-bottle. In order to solve such problems with a Chinese herbal medical preparation, it is considered to make a Chinese herbal medicine in the form of jelly.
As a jelly preparation containing a Chinese herbal medicine, there is known a jelly preparation made of a Chinese herbal medicine and gelatin (Japanese patent publication B 7-116049). As gelatin is a gelling agent which is physico-chemically unstable, the preparation lacks preservative stability and must be stored in a cold place. Therefore, it does not stand for the test for medicines (the long term-preservation test at 25° C. under 60% RH for 3 years, or the accelerated preservation test at 40° C. under 75% RH for 6 months, etc.). In addition, gelatin is easily dissolved in a mouth and therefore, the preparation easily gives the bitter taste and is difficult to take when a Chinese herbal medicine having the strong bitter taste is contained.
In addition, it is considered that a jelly preparation containing Chinese herbal medicine is prepared using sodium alginate or agar. As a jelly preparation containing a Chinese herbal medicine using sodium alginate, a jelly preparation containing Sho-saiko-to is known () (Japanese patent No. 2508547). The bitter taste peculiar to a Chinese herbal medicine can be masked by adding alginic acid. However, as jelly containing alginic acid causes much syneresis, heterogeneity of the drug occurs and the drug remains in the packed vessel when taking it. The appearance is also bad. Therefore, the preparation is not preferable as a medicine.
In regard to a jelly preparation prepared using agar, the preparation causes much syneresis, similar to the preparation containing alginic acid. Further, the preparation easily disintegrates in a mouth, easily gives the bitter taste and does not give a good feeling when taking it.
As other jelly preparations, a jelly composition (Japanese patent publication A 9-187233 and Japanese patent publication A 9-194346) and a Chinese herbal medical composition in the form of jelly (Japanese patent publication A 2001-114696) are known, but it is very difficult to prepare jelly preparations containing a Chinese herbal medicine which guarantees the preservative stability on a medical level.
The following reasons are considered as causes which make it difficult to make a Chinese herbal medicine in the form of jelly.
The preparation contains as a starting material, a natural product which consists of a variety of ingredients, and many of these ingredients are structurally unknown. In addition, there are many forms of starting materials, such as crude drugs, liquid extract, condensed extract, dry extract, soft extract, fluid extract, etc., and the dosages on them vary.
As there is such a background peculiar to a Chinese herbal medicine, when a Chinese herbal medicine is formed into a jelly preparation, according to the kind or amount of the contained Chinese herbal medicine, there are possibilities to produce the preparation wherein its appearance can not be maintained due to syneresis and the stability of the active ingredients can not be maintained. Therefore, a Chinese herbal medical composition in the form of jelly which is broadly applicable has been desired.